At 8/9/2008 17:58, you wrote: >I watched a cable TV system installation on a 300 ft tower many years >back, and it was interesting to see where the receive antennas were >placed. We had channels 4,5,8,11, and 13. > >The tech took a portable antenna and receiver up the tower and watched the >signal strength for each channel as he climbed, and placed a marker on the >tower for the FIRST peak he found in signal strength. He started on ch 4 >and that antenna position was at about 100 ft. We were about 70 miles >from the TV stations. > >As he worked his way up the channels the ch 13 antenna wound up at about >200 ft. All these points were at the first peak he found going up the >tower. As he climbed above that point, the signal strength would go down >for a given channel, as the ground reflection was starting to cancel out >the direct signal, or was no longer adding to the direct signal, whichever >way you want to look at it. > >I thought this might be interesting to the group -
Yes. But what about multipath? Ground reflection "adding" to the direct path can result in severe ghosting. Bob NO6B
